The number 8 is generally considered a good luck number by the Asian community, just like the number 7 is considered good luck in North America.

That's why you see 888 as the number of chips issued as well (more good luck). And you tend to see 777 as the winning combination on slots.

There is starting to be a fair number of $8 chips now being issued. I've got 10 so far from Nevada alone and know of just 3 others I don't have (including this new one from Palms).